NestJS nduwé GraphQL support tingkat-pertama (first-class) liwat @nestjs/graphql (dibangun liwat Apollo Server). Njajakaké pendekatan code-first (gawé schema nganggo TypeScript classes lan decorators, schema otomatis digenerate) — cara idiomatic NestJS — pas karo model decorator/DI framework.
({
: [
.<>({
: ,
: ,
: ,
}),
],
})
{}
@ObjectType() // a GraphQL type
export class User {
@Field(() => ID) id: string;
@Field() name: string;
@Field() email: string;
@Field(() => [Post]) posts: Post[]; // related type
}
Dadine code-first, classes sing dibedani (@ObjectType, @Field) gawé schema — TypeScript types nggawe GraphQL schema otomatis, njaga supoyo tetep sinkron.
@Resolver(() => User)
export class UsersResolver {
constructor(private usersService: UsersService) {} // DI works as usual
@Query(() => [User]) // a query: returns a list of users
users() {
return this.usersService.findAll();
}
@Query(() => User)
user(@Args("id") id: string) { // query with an argument
return this.usersService.findOne(id);
}
@Mutation(() => User) // a mutation: creates a user
createUser(@Args("input") input: CreateUserInput) {
return this.usersService.create(input);
}
}
Resolvers (kaya controllers, nanging kanggo GraphQL) gawé @Query lan @Mutation handlers, delegasi menyang services liwat DI — pola-pola sama karo REST controllers.
@ResolveField(() => [Post]) // resolve User.posts on demand
posts(@Parent() user: User) {
return this.postsService.findByUser(user.id);
}
// ⚠️ for lists, this can cause N+1 queries → use DataLoader to BATCH them
@ResolveField ngrusuké related/nested fields kanthi lazy — nanging kanggo lists, iki bisa risiko N+1 query problem, dipecah karo DataLoader batching.
GraphQL: clients request EXACTLY the fields they need (no over/under-fetching),
one endpoint, strongly typed, great for complex/nested data & varied clients
REST: simpler, better HTTP caching, well-understood — fine for straightforward APIs
→ Choose based on needs, not hype. NestJS supports both equally well.
NestJS support GraphQL tingkat-pertama sing idiomatic penting amarga ngebawa manfaat GraphQL — clients njupuké data sing persis mereka butuhake (ngilangi over- lan under-fetching), one strongly-typed endpoint, lan excellent handling data kompleks/nested — menyang NestJS model sing familiar, terstruktur.
Paham iki penting kanggo nggawe APIs modern, utamane pendekatan idiomatic code-first (gawé schema nganggo TypeScript classes lan @ObjectType/@Field/@Resolver decorators, schema otomatis digenerate lan tetep sinkron) sing pas karo NestJS decorator/DI architecture secara natural — resolvers kerja kaya controllers, delegasi menyang injected services.
Ngerti carane gawé types, queries, mutations, lan resolved fields, lan aware marang N+1 query problem (lan DataLoader minangka solusi) kanggo data nested, minangka key senior-level knowledge.
Samaning penting banget iku ngerti GraphQL vs REST trade-offs supaya pilih pendekatan sing tepat kanggo project tartamtu (GraphQL kanggo flexible, kompleks, multi-client data needs; REST kanggo APIs simpel karo strong HTTP caching).
GraphQL minangka major API paradigm, lan NestJS clean integration ndadekake meaningful, frequently-relevant capability kanggo nggawe flexible, efficient back-ends.